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Prosthetic Concept of Resilient Construction
Prosthetic
Concept of Rigid Construction
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The
Implant retained overdenture
Function, esthetics, and stability. Those are
the three key words when fabricating an implant retained overdenture.
And when it comes to patient satisfaction, a stable and comfortable fit is
undoubtedly the decisive factor. With multiple implants, the position
of the bar with respect to the tooth arrangement is extremely important to
avoid tilting movements. The case study presented here is based on a
prosthetic concept which fully considers this principle. The concept
has already been successfully applied for many years around the world.
Its simplicity and flexibility allow its use in widely divergent situations. |
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The
basic idea
When planning a bar construction, the position of the
dental arch--and not of the implants--is the point of departure. In
the anterior area as well as premolar and molar region, the bar is placed
underneath the teeth. Moreover, it is extended in dorsal direction
while reducing the dental arch. Under ideal conditions, the dorsal bar
extension coincides with the terminal prosthetic element.
What goes for a normal overdenture also goes here.
This means that the retromolar pad and the maxillary tuberosity must always
be covered. The palate usually remains free.
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The dorsal bar extension |
- The Green Tangent lines
at the implants form a plane through which a blue
dotted centre line runs.
- The blue dotted centre line
intersects the vertical center line in Point
A1. The vertical center line is
at right angles to the hinge axis.
- The distance between A2 and A3 is
approximately half as much as the distance between A1 and A2.
- A line through Point A3
runs parallel to the hinge axis.
- The ridge intersections indicate the maximum
extensions. Up to these points, the prosthesis can be supported by
the bar surface.
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Stability
On this case, the stability of the prosthesis is
guaranteed by (tripod) three parts: 1) the two distal attachments, 2) the
anterior Hader bar attachment, and 3) the dental arch which is almost
completely supported by the bar.
For maxillary constructions, the palate remains free.
The extensions of the acrylic resin into the vestibule considerably improves
the facial physiognomy--which is often impossible with bridges. The
fact that the prosthesis is removable offers advantages such as oral hygiene
and servicing.
The implant retained overdenture is an excellent
alternative for fixed or screwed bridges. |
Ceka Implant Bar Constructions
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angled female of choice as an extension of the wax bar (FIG
1). The attachments are
not loaded when the space maintainers are used. The support zones are located over
the implants for axial loading (FIG
2). Use a two stage investment technique.
Allow the initial investment to set for 30 minutes (FIG
3). |
| Bar and attachments are milled at an angle of 4 degrees, or
the 8 degree tapered plasti-wax bar pattern may be used (FIG
4). The support zone
(arrow) is over the implant for axial loading (FIG
5). The attachment is not
loaded. Preparations for the spacer technique are made as usual.
The space maintainer (arrow) is used to avoid loading any attachments (FIG
6). |
| Not the rounded tissue side of the female for easy patient
hygiene and maintenance (FIG
7). When space between implants is minimal, use the
inverted REVAX axial attachment (FIG
8).
The titanium females are bonded into the cast bar (FIG
9). |
| The spacer retention technique is used on this case (FIG
10 and
11). The attachments all have been processed using the small space maintainer.
The loading is only at the elevations on the bar (arrows,
FIG 12). |
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